Effects of infection by larvae of Angiostrongylus cantonensis (Nematoda, Metastrongylidae) on the lipid metabolism of the experimental intermediate host Biomphalaria glabrata (Mollusca: Gastropoda)

Abstract

Experimental infection of Biomphalaria glabrata by Angiostrongylus cantonensis induces significant changes in the concentrations of triacylglycerol and cholesterol in the hemolymph and of neutral lipids in the digestive gonad-gland (DGG) complex of the host snail. In this study, snails were dissected after 1, 2, and 3 weeks of infection to collect the hemolymph and DGG and to measure the levels of cholesterol and triacylglycerol in the hemolymph and neutral lipid fractions in the tissues. The results show that infection by this nematode resulted in a significant decrease in the concentrations of both cholesterol and triacylglycerol in the hemolymph of B. glabrata during the parasite's initial ontogenic development period. This reduction indicates the possible use of these molecules by both parasite and host not only as energy substrates but also as structural factors required during development of the parasite's larval stages. In parallel, changes in the neutral lipid profile in the DGG and lipase activity of the infected snails were observed, indicating the importance of these molecules for successful infection.

Alterations in lipids and minerals in relation to larval trematode infections of Nerita polita marine snails

“…Tunholi et al, 2011;Tunholi-Alves et al, 2012;Tunholi-Alves et al, 2013;Alves et al, 2014). TunholiI- presented similar results in their study on the infection of Biomphalaria glabrata by Echinostoma paraensei.…”

Influence of exposure Heterorhabditis bacteriophora HP88, (Rhabditida: Heterorhabditidae) on biological and physiological parameters of Pseudosuccinea columella (Basommatophora: Lymnaeidae)

“…In the histopathological evaluation of the snails in the control group, there were no alterations (Figure S3 supplementary material); In addition, the presence of glycogen was strongly marked by PAS staining, as shown in images A and C. On the other hand, in snails exposed to H. bacteriophora HP88, alterations mainly established in the digestive gland were observed (Figure S3D supplementary material), characterized by the weak presence of glycogen, multifocal vacuolation and cell lysis. Tunholi-Alves et al (2013) reported that A. cantonensis infection also induced important histological changes in the digestive gland of B. glabrata. According to the authors, the organ in question has a remarkable ability to synthesize glycogen, proteins and lipids, providing in abundance essential nutrients for the evolution of the larval stages of the nematode, representing the main site of parasitic development.…”

“…In the present study, snails exposed for 24h were able to restore their glucose concentrations to levels similar to those of the control in the third week of analysis, thus suggesting the existence of homeostatic mechanisms involved in the control of glucose, denoting the ability of these hosts to adapt to this physiological stress condition. Such metabolic plasticity was described by Thompson & Lee (1986) in the B. glabrata/Schistosoma mansoni interface and by Tunholi-Alves et al (2013) studying the relationship between B. glabrata and A. cantonensis.…”

“…In the cephalopodal mass (Figure S3B Supplementary material), a weak presence of glycogen, multifocal vacuolation, cell lysis and structural disorganization was observed. Tunholi-Alves et al (2013) reported that the reduction in the amount of galactogen stored in the albuminous gland of snails results in a low hatching rate, characterizing the phenomenon of reduced fertility. Galactogen is an isomer of glycogen, being the only polysaccharide that integrates part of the perivitelline fluid of gastropods, used as a source of nutrients in the development of embryos before and after hatching.…”

Analyses of single nucleotide polymorphisms in Angiostrongylus cantonensis based on transcriptome sequencing.

“…It is now epidemic in a very wide region of the world, including Asia, the Pacific Islands, the Caribbean islands and Brazil. During the past decade, more than 2,800 cases of human infections and several human angiostrongyliasis outbreaks have been reported and which declared it as a public health problem that cannot be neglected [1].…”